Aurora towns in Uusimaa

The widest gap in the dipole ranking falls between Hyvinge and Mäntsälä, 0.1 degrees. 12 neighbouring pairs sit within 0.5 degrees of each other, close enough that the order between them means little.

Of the 13 indexed towns in Uusimaa, 13 sit between 55 and 60 degrees, where G1 (Kp 5) or less usually brings aurora into view.

On December 15 the median town gets 16.1 hours of civil night, against 16.3 nationally. Hyvinge has the most at 16.1 hours and Raseborg the least at 16.0. 12 of these towns lose civil darkness altogether around the June solstice; Hyvinge goes longest, 26 nights.

NASA POWER's 2001 to 2020 climatology puts median cloud amount in the dark months at 74%, against 76% nationally. Hyvinge is clearest at 74% and Raseborg cloudiest at 74%. These are all-hours averages for 1 degree cells, not forecasts.

Multiplying civil night by the clear share of the sky, March comes out best for 13 of the 13 towns. SWPC notes a tendency toward larger storms near the equinoxes, which this score does not include.